I have a question about the ever increasing use of the 2.55:1 aspect ratio and wider on music videos and commercials.

To make my question a little clearer here is an example:

Toro Y Moi — "So Many Details"

This video was shot anamorphically with the LOMO anamorphics. Judging by the final aspect ratio would it be reasonable to guess that it was shot on Super35 with anamorphic lenses and then desqueezed to achieve what appears to be 2.55:1? I was wondering whether if this is the case, they would have needed a custom ground glass to ensure that framing was possible without say centring the system for sound aperture, using an anamorphic GG, then estimating where the centre of frame would be so that your footage ends up centre once it has been desqueezed in the wider format.

Of course they could have simply cropped the 2.39:1 image to give the extra width...